Foldable step stool



FIG. 1 is a top, front and end perspective view of the foldable step stool showing my new design;

FIG. 2 is a front elevational view thereof, the rear being a mirror image of the front shown in FIG. 2;

FIG. 3 is an end elevational view thereof, the end opposite being a mirror image of the end shown in FIG. 3;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a foldable step stool, as shown and described. 